Debug : File :i386\chkesp.c ERROR

[psree]

Hi

Below is the snippet of the code

C/C++ Prototype

extern “C” short FAR PASCAL RP1210_ClientConnect
(
    HWND hwndClient,
    short nDeviceID, 
    char far* fpchProtocol,
    long lTxBufferSize,
    long lRcvBufferSize,
    short nIsAppPacketizingIncomingMsgs  
);
 

when we are trying to call the above prototype function RP1210_ClientConnect. in VC++ as shown below to build a dll and when we are calling the DLL function we are facing a problem
---------------------------------------------------------------
Debug Error:

Module:
File:i386\chkesp.c
Line :42

The Value of ESP was not properly saved across a function call.............
--------------------------------------------------

DLL Code given below

typedef short (*MYPROC_RP1210_ClientConnect)(HWND,short,char far*,long,long,short);
 
short VT_CA2ClientConnect(HWND hwndClient,short nDeviceID, 
                                                char *fpchProtocol,
                                                long lTxBufferSize,
                                                long lRcvBufferSize,
                                                short nIsAppPacketizingIncomingMsgs )
{
 
    AFX_MANAGE_STATE(AfxGetStaticModuleState());  
    HINSTANCE    hinstlib; 
    BOOL    fRunTimeLinkSucess = FALSE; 
    //BOOL fFreeResult;
    MYPROC_RP1210_ClientConnect    ClientConnnectprocAdd ;
 
    short lError = 0;
 
    hinstlib = LoadLibrary("ca2rp32");
    //if handle returns success
    if( hinstlib != NULL){
        //get the function address
        ClientConnnectprocAdd = (MYPROC_RP1210_ClientConnect) GetProcAddress(hinstlib, "RP1210_ClientConnect");
        //call the function
        if(fRunTimeLinkSucess = (ClientConnnectprocAdd != NULL))
            lError    = (ClientConnnectprocAdd)(hwndClient,nDeviceID,fpchProtocol,lTxBufferSize,lRcvBufferSize,nIsAppPacketizingIncomingMsgs);
    }
        //free all handles
        //fFreeResult = FreeLibrary(hinstlib);
    return lError;
 
}

-----------------------------------

Please can anyone help me to find the solution.

[weaknessforcats]

I expect your function name is being mangled.

Try a adding DEF file in your dll project to export your mangled name as an unmangled name. Here's an example:

;BEGIN ADLL.DEF FILE
;This DEF file is required because the argument to GetProcAddress()
;for the function is a C-string and it will never be equal to the
;C++ mangled name for the function
;This DEF file maps the mangled name to a name that can be used with GetProcAddress()
;Note also: Change project settings in Visual Studio to send the LINK this def file.
;Visual Studio.NET: Project Properties/Linker/Input/Module Definition File/...Path to the def file\Adll.def
LIBRARY ADll 
EXPORTS 
;Exported Name    C++ Mangled Name
AreaOfSquare   =  ?AreaOfSquare@@YGHHH@Z
DisplayFromDll =  ?DisplayFromDll@@YGXXZ
;END DEF FILE 
 

[ManishaT41]

This i386/chkesp debug error occurs when there is stack overflow in the code . Use debug step by step mechanism to find out at what actual point , the error occurs. you can trap that array or string which causes stack overflow.
Also clean up watch and debug directory and try . Remove only .obj and .sbr files .. take backup before u clean.

But trap the wrong code and correct it.

[weaknessforcats]

I just noticed that RP1210_ClientConnect is not a function. It's an extern "C" block.

The OP is not checking the return from GetProcAddress to see of it worked.